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With Volvo Scan Tool

Read-outs with Volvo Diagnostics






Data on any faults and other information can be read out with the Volvo ST connected to the DLC on the console in front of the gear lever. The Volvo ST communicates with the control module via a standardized communications program.

You can use the Volvo ST to:
Read out and erase posted DTCs, the counter and frozen values.
Read out control module input and output signal values and status continuously.
Read the control module ID.

The DLC is common to both Volvo Diagnostics and the less sophisticated diagnostic system OBD II, On Board Diagnostics II (OBD II some markets only, US/CDN).






Connecting the Volvo ST:

Ignition off.
Install memory module
Connect Volvo ST by loads to DLC in console in front of gear lever.
Ignition on
Switch power on to Volvo ST.
Select language, model, tunction group.
Select system.
Select operation (read, erase, DTCs, activate components etc.).

To activate Volvo Diagnostics:






Ignition must be on.
Battery voltage must be normal.
Speed of all wheels must be less than 10 km/h (6 mph).
The control module must not have activated ABS, EBD or TRACS.

Once the control module has activated Volvo Diagnostics, the ABS warning light will start flashing at a frequency of 2 Hz.

When activation of Volvo Diagnostics ends, the warning light stops flashing and the control module returns to its normal position for ABS, EBD and TRACS.

Reading out and erasing DTCs

This service can be used to read out and erase DTCs posted, counters and frozen values. The diagnostic system can identify 33 different faults in the form of DTCs (35 with TRACS). For fault-tracing DTCs see DTC table Antilock Brake System (ABS). No DTCs can be erased until all DTCs posted have been read out at least once during the same diagnostic session.

For each DTC, the frozen values can be read out for the following parameters:

The car's reference speed
Brake light switch status
ABS/EBD/TRACS status

For more details of frozen values see [LLLB]. Frozen values with DTCs. Frozen values with DTCs. Pinout Values and Diagnostic Parameters

Activation of components/systems

The system components can be activated individually with this service. Activation is only possible where all wheel speeds are 0 km/hr. The activation is interrupted at speeds above 0 km/hr

The following components can be activated:

ABS/TRACS warning light
Pump motor
Outlet valve rear wheel
Inlet valve rear wheel
Outlet valve RH front wheel
Inlet valve RH front wheel
Outlet valve LH front wheel
Inlet valve LH front wheel
Inlet valve TRACS

Note! Activation cannot be carried out if DTC ABS-445 Pump motor is posted permanently

For more information on activation see [LLLB]. Frozen values with DTCs Pinout Values and Diagnostic Parameters

Reading input and output signals

This service can be used to read out the values and status of the control module input and output signals continuously. The parameters are divided into three predefined lists. The division is made so that parameters in list 1 and 2 are updated by the control module at the same time. The parameter values thus reflect driving conditions at the same time and are directly comparable with one another.

The following parameters can be read out:

List 1

Wheel speed LH front wheel
Wheel speed RH front wheel
Wheel speed LH rear wheel
Wheel speed RH rear wheel
Extrapolation counter LH front wheel
Extrapolation counter RH front wheel
Extrapolation counter RH rear wheel

List 2

The car's reference speed
The car's reference acceleration
Wheel speed LH front wheel
Wheel speed RH front wheel
Wheel speed LH rear wheel
Wheel speed RH rear wheel
Wheel acceleration LH front wheel
Wheel acceleration RH front wheel
Wheel acceleration LH rear wheel
Wheel acceleration RH rear wheel

List 3

ABS warning light
Brake light switch, position
EBD pressure sensor, position

And in cars with TRACS:

TRACS warning light
TRACS switch

For more information on parameters see [LLLA]. Running values, Volvo System Tester Running values, Volvo ST Pinout Values and Diagnostic Parameters

Read Control module ID

The Volvo System Tester identifies the control module by reading a code from the control module's memory. This code is made up of two figures, a software number and a hardware number.